Same as down. Used primarily by Unix
hackers. Humorous: also implies a condition thought to be relatively easy
to reverse. Probably derived from the Canadian slang ‘hoser’
popularized by the Bob and Doug Mackenzie skits on SCTV, but this usage
predated SCTV by years in hackerdom (it was certainly already live at CMU
in the 1970s). See hose. It is also widely used of
people in the mainstream sense of ‘in an extremely unfortunate
situation’.

Once upon a time, a Cray that had been experiencing periodic
difficulties crashed, and it was announced to have been hosed. It was
discovered that the crash was due to the disconnection of some coolant
hoses. The problem was corrected, and users were then assured that
everything was OK because the system had been rehosed. See also
dehose.